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The aim of this work is to apply an innovative adaptive ℒ1 techniques to control flutter phenomena affecting highly flexible wings and to evaluate the efficiency of this control algorithm and architecture by performing the following tasks: i) adaptation and analysis of an existing simplified nonlinear plunging/pitching 2D aeroelastic model accounting for structural nonlinearities and a quasi-steady aerodynamics capable of describing flutter and post-flutter limit cycle oscillations, ii) implement the ℒ1 adaptive control on the developed aeroelastic system to perform initial control testing and evaluate the sensitivity to system parameters, and iii) perform model validation and calibration by comparing the performance of the proposed control strategy with an adaptive back-stepping algorithm. The effectiveness and robustness of the ℒ1 adaptive control in flutter and post-flutter suppression is demonstrated.

A Web-based version of the aircraft design program ACSYNT has been created. “Web-ACSYNT” provides the user with a familiar user interface and is accessible from multiple platforms. Analyses are based upon a set of baseline aircraft models which can be modified through a carefully selected set of parameters related to weight, aerodynamics, propulsion, economics, and mission. The software is intended to become one of the models that comprise the Aviation System Analysis Capability (ASAC) currently being developed by NASA under the Advanced Subsonic Technology (AST) program.

This paper presents, chemistry, test data and processing procedures on a non toxic and environmentally friendly chrome-free conversion coating alternative with the same level of adhesion and secondary corrosion resistance as that found in chrome containing conversion coating systems. Test data from military and independent sources will be presented on secondary coating adhesion, electrical conductivity, filiform and neutral salt-spray corrosion resistance as compared to chromate based systems .on magnesium, aluminum and zinc and their respective alloys. The European “RoSH” initiative will not allow for the presence of any hexavalent chromium on imported electrical components as of July first of 2006. Trivalent chromium based systems generate hexavalent chromium due to the oxidation of the trivalent chromium and as such will not be allowed.

In automotive electronics on-board diagnostics does the fault diagnosis and reporting. It provides the level of robustness required for the control electronics against various faults. The amount of diagnostic information available via on board diagnostics are depends on the type of vehicle. Pre-supply fuel pump is the component in the common rail hydraulic system. It pumps the fuel from the fuel tank to the inlet valve of the high pressure fuel pump. Electronic control unit synchronizes its operation with high pressure fuel pump. A dedicated driver module in the ECU controls the operation of pre-supply fuel pump. The driver module consist of an ASIC with internal voltage, current monitoring modules for the fault diagnosis and the pre-drivers to control external HS and LS power stages. The software part of the OBD programmed in the internal memory of the ASIC. The “Rds_on” of the power MOSFETs are used for the fault detection purpose.

MONOGAL is a coated steel developped to improve the corrosion resistance of exposed automotive body applications. Its process os based on the brittleness of the η zinc coating in a range of temperatures below the melting point of the zinc. MONOGAL is produced on a hot dip galvanizing line; at the exit of the pot the free zinc is brushed off the light side of the differentially coated sheet. Side 1 of MONOGAL presents a very thin and continuous layer of iron-zinc diffusion alloy with no free zinc. Side 2 is a standard G90 or G60 zinc coating. The iron-zinc alloy layer has excellent anti-galling properties which improve the formability of MONOGAL over two side hot dip galvanized steel with the same r value. MONOGAL also shows good weldability, paintability and corrosion resistance.

Affordable, efficient and durable catalytic converters for the two and three wheeler industry in developing countries are required to reduce vehicle emissions and to participate in a cleaner and healthier environment. As a contribution Continental Emitec started a comprehensive testing program with a state of the art 180 cc Bharat Stage (BS) III Indian motorcycle. The program consists of testing the state of the art of Metallic substrates with structured foils with various catalyst sizes and positions (original or close coupled). The publication presents a short literature survey and the results of the investigation with a big catalyst volume mounted in underfloor position as well as in close coupled position, gained over the World-wide harmonized Motorcycle Test Cycle, considering the two possible vehicle classifications of this motorcycle, Sub-Class 2.1 and Sub-Class 2.2.

THIS STANDARD ESTABLISHES THE DIMENSIONAL AND VISUAL QUALITY REQUIREMENTS, LOT REQUIREMENTS, AND PACKAGING AND LABELING REQUIREMENTS FOR D-RINGS MOLDED FROM MIL-P-25732 ACRYLONITRILE BUTADIENE (NBR) RUBBER. IT SHALL BE USED FOR PROCUREMENT PURPOSES.

Design of a Cabin Tilting System of heavy trucks, a multi degree of freedom mechanism, is a challenge. Factors like adequate tilting angle, cabin styling, packaging, non interference of tilting system with ride comfort, forces in the system, specifications of the hydraulic system, are all very important for designing the system. Numerous considerations make the design process highly iterative hence longer design time. This paper primarily focuses on Kinematics and Dynamic analysis of the system in ADAMS and validation of system with real time testing results. Intention of this work is to make a parametric ADAMS model and link it to a Knowledge Based Engineering application to facilitate designer to quickly carry out design iterations for reducing development time. The Knowledge Based Engineering software is made using object oriented language called ‘Object Definition Language’ which has been developed using C and C++ software languages.

“DELRIN” is a new thermoplastic which offers high strength, excellent thermal stability, good fatigue life, low creep, and excellent solvent resistance. This paper describes the physical and chemical properties of the material, and the range of possible uses. The material is easily fabricated into complex shapes by standard injection-molding techniques. Also, it can be easily joined to itself or to other materials. The authors think that the material offers advantages over metals in its good fric-tional properties, abrasion resistance, and corrosion resistance.

The objective of the development of the aerodynamic drag predictive tool CDaero was for use as a module for the Automobile Design Support System (AutoDSS). CDaero is an empirically based drag coefficient predictive tool based initially on the MIRA (Motor Industry Research Association) algorithm. The development philosophy was to be able to predict the aerodynamic drag coefficient of an automobile with knowledge of the features of the surface geometry control curves. These are the curves that control the 3-dimensional geometry as seen in the profile, plan and front and rear views. CDaero has been developed in a computing environment using the equation solver TKSolver™. Fifty-one input feature values are first determined from the automobile geometry and then entered into the program. CDaero models the drag coefficient with thirteen different components covering the basic body, as well as additional components such as the wheels, mud flaps, etc.

3-D Flow separations such as those that occur on the rear end of a vehicle have an impact on wall pressure distribution, hence on aerodynamic forces. The identification of these phenomena can be made through the analysis of skin friction patterns, which consist of the “footprints” of flow separations. These can be determined from qualitative and quantitative data obtained from near-wall PIV measurements. The wake flow of different configurations of a simplified 1/4 scale car model are analyzed. The influence of the slant angle and the Reynolds number on 3-D separated flow patterns and their induced pressure distribution is addressed, based on near-wall PIV, standard PIV and wall pressure measurements. This enables to understand how a topological change (the size or shape of a separation pattern) modifies the associated pressure distribution (therefore the drag coefficient). Finally, insights into instantaneous topology identification are presented.

This recommended practice prescribes clear and consistent labeling methodology for communicating important xEV high voltage safety information. Examples of such information include identifying key high voltage system component locations and high voltage disabling points. These recommendations are based on current industry best practices identified by the responder community. Although this recommended practice is written for xEVs with high voltage systems, these recommendations can be applied to any vehicle type.

THE DEVELOPMENT of new polymers offering properties and new combinations of desirable characteristics, coupled with advances in manufacturing techniques, has expanded the plastics horizon. This paper describes some of these new materials and a few of their many possible applications in the automotive industry. The author emphasizes that greater use of plastics in the automotive field depends to a great degree on the imagination and ability applied in creating new products. Design features most overcome the fundamental limitations of the new materials. The basic weaknesses of plastics are listed. Production techniques will affect the future expansion of the industry. Three methods show particular promise: blow molding, fluidized polymer deposition, and potting compounds.*

IF ROCKET OR MISSILE designers were asked to choose one specific property of engineering materials they would like to have improved, the largest percentage would undoubtedly select strength at high temperature. In addition to retaining strength at high temperatures, missile materials must be resistant to erosion and ablation. Missile structures must also be satisfactory when subjected to aerodynamic and acceleration loads, high stresses of vibration, and thermal shock. The need for low-density, easily fabricated, heat-resistant materials has resulted in a continuing search for more effective combinations of known materials, as well as the development of new materials. This paper discusses some interesting results obtained in studies of composite materials that might be used for rocket or missile construction.

STRUCTURAL MATERIALS for Mach 3 jet transports pose difficult problems for the design engineer. Reasons for this problem are the incomplete information available on the many possible metals and the diversity of critical properties that are added by supersonic requirements. The material properties discussed in this paper include tensile strength, resistance to crack propagation, ease of fabrication, weldability, and thermal expansion. Cost factors are also considered. The structural configuration of the wing and fuselage is an example of the complexity of the material selection problem. The wing may be rigidity-critical, and the fuselage strength-critical; each requires diferent material properties to solve the problem.*

NEW WELDING processes are dropping costs while providing improvements in weld quality. This paper describes some of the more promising new developments in pressure and fusion welding and brazing. Included in the discussion are ultrasonic, high frequency resistance, foil seam, magnetic force, percussion, friction, and thermopressure welding and diffusion bonding. The description of adhesive bonding includes the development of glass or ceramic materials as structural adhesives.*

The main purpose of this study is the development of an innovative methodology for Heat Exchangers (HE) design to replace the conventional design procedures. The new procedure is based on the definition of a software package managed by modeFRONTIER, a multi-objective optimization software produced by ESTECO, able to create HE virtual models by targeting several objectives, like HE performance, optimal use of material, HE minimal weight and size and optimal manufacturability. The proposed methodology consists first in the definition of a workflow for the automatic CFD simulation of a parametric model of a periodic HE cellular element.

THIS PAPER is concerned with design problems which are encountered on manned aircraft operating at very high speeds. Very high speeds are considered to be from Mach 2 or 1300 mph to speeds of the order of Mach 38 or 25,000 mph, which is the velocity for escape from the earth. Mach 2 is considered a logical starting point since it represents the approximate upper limit of present day military aircraft. Manned aircraft will continue to be developed for flight at very high speed and high altitudes and the experiences gained will serve as stepping stones to eventual manned satellites and space vehicles. The major problems to be solved relate to aerodynamic heating, stability and control, and human effects. This paper received the 1958 Wright Brothers Medal.

In a 2-year program sponsored by SJAC, an aqueous electroplating process using alkaline Zn-Ni with trivalent chromium post treatment is under evaluation for high strength steel for aircraft application as an alternative to cadmium. Commercial Zn-15%Ni rack/barrel plating solutions are basis for plating aircraft parts or fasteners. Brightener was reduced from the original formula to form porous plating that enables bake-out of hydrogen to avoid hydrogen embrittlement condition. Properties of the deposit, such as appearance, adhesion, un-scribed corrosion resistance, and galvanic corrosion resistance in contact with Al alloy, were evaluated. Coefficient of friction was compared with Cd plating by torque-tension measurements. Evaluation of the plating for scribed corrosion resistance, primer adhesion, etc. will continue in FY2007.